Method of packaging tubular stencils

ABSTRACT

A method of packaging a screen printing cylinder comprises the steps of positioning an expansible or extensible bag or bags within the interior of said cylinder and filling said bag or bags under pressure so as to form a substantially rigid body or bodies which bear firmly against the wall of the printing cylinder, or a part or parts thereof, to reinforce it against inward crushing or collapse. Conveniently said printing cylinder is the inner of an assembly of such cylinders and is temporarily deformed to a flattened oval shape, the cylinders within it being temporarily deformed to a shape of kidney-like cross-section. This enables a plurality of printing cylinders of the same diameter to be packed one within another for transit. Conveniently the bag or bags is or are filled under pressure with small beads of an expanded polymeric material, the bag or bags being of a flexible plastics material. The invention also provides a transit package having packed within it a screen printing cylinder or an assembly of such cylinders by the method above described.

United States Patent Burdis Dec. 30, 1975 METHOD OF PACKAGING TUBULAR STENCILS Primary ExaminerLeonard Summer 75 l t R St B d' nven or Egglantmer ur 1s, Tarporley, ABSTRACT I v A method of packaging a screen printing cylinder [73] Asslgnee' Screemex Helens comprises the steps of positioning an expansible or ex- England tensible bag or bags within the interior of said cylinder [22] Fil d; 11 4 and filling said bag or bags under pressure so as to form a substantially rigid body or bodies which bear [2H Appl' 441,440 firmly against the wall of the printing cylinder, or a part or parts thereof, to reinforce it against inward [30] Foreign Application priority Data crushing or collapse. Conveniently said printing cylin- Mar. 2, 1973 United Kingdom 10227 73 def is the.inner of an assembly of such Cylinders and is temporarlly deformed to a flattened oval shape, the 52 U.S. c1. 206/446; 53/3; 206/522; Cylinders Within l being temPorarily. deformed to 3 206/523 shape of kidney-like cross-section. This enables a plu- 51 Int. cm .1365!) 85/30; B65D 81/12; of l Fylinders of the diameter?) be B65B 19/00 packed one with n anothenfor transit. Conveniently [58] Field of Search 206/522, 523, 524, 446 the bag or bags or are fined prassule small beads of an expanded polymeric material, the [561 References Cm En i25:11;2?;33352 2 iiafilti gifiigi lilfig UNITED STATES PATENTS packed within it a screen printing cylinder or an as- 3,085,608 4/1963 Mathues 150/1 sembly of such cylinders by the method above d6- 3,372,s01 3/1968 Wagter 206 446 Scrum] 3,380,577 4/1968 Washburn 206/522 X 3,450,253 6 1969 Nielsen 206 524 8 Clams, 3 Drawing Figures 3,503,177 3/1970 Krapscott et al. 206/524 X US, Patent Dec. 30, 1975 Sheet 1 of2 3,929,227

US. Patent Dec. 30, 1975 Sheet 2 of2 3,929,227

METHOD OF PACKAGING TUBULAR STENCILS This invention is for improvements in or relating to the packaging of tubular (e.g. cylindrical) and like stencils hereinafter referred to as screen printing cylinders.

Screen printing cylinders are used extensively in the colour printing of textile fabrics, carpets, wallpapers and the like. Having regard to the amount of work and skill and consequential cost involved in the making of screen printing cylinders, it is most important that they should be well protected against damage during transit from, for example, the place of manufacture to the place where they are to be used.

According to the present invention there is provided a method of packaging a screen printing cylinder which includes the steps of positioning an expansible or extensible bag within the interior of the screen printing cylinder and filling said bag under pressure so that it will form a substantially rigid body which bears firmly against the wall of the printing cylinder or a part or parts thereof, to reinforce it against inward crushing or collapse.

in one preferred method of carrying the invention into effect a plurality of screen printing cylinders, all of the same diameter, are, for packing purposes, temporarily deformed, e.g. the outer one to a flattened oval shape and the inner ones to a shape of kidney-like cross-section, so that they can be inserted and will fit snugly one within another. This assembly of printing cylinders is enclosed in a packing case of rectangular cross-section in which the assembly is a relatively snug fit. Two elongated bags in parallel relationship and in an initially flat condition, are then passed through the interior of the assembly of cylinders. The bags are then filled under pressure so that they take on, at least in part, the interior contour of the assembly of cylinders and bear firmly and rigidly against the interior wall thereof.

The bag preferably is filled under pressure with a suitable material in particulate, granular or like form. One such material, which has been found very suitable for the purpose of the invention, consists of beads of an expanded polymeric material e.g. polystyrene. Preferably the beads are relatively small e.g. have a diameter of the order of one-sixteenth inch to one-eighth inch.

One convenient material of which the bags may be made is polyethylene, available commercially for example as POLYTHENE (Registered Trade Mark). The wall of the bag is perforated, preferably with a multiplicity of very small perforations, so as to allow air to escape where the bag is being filled under pressure with the beads of polystyrene or other material.

Conveniently the ends of the bags are caused to project beyond the ends of the assembly of printing cylinders so as to prevent damage to the cylinders should the package be dropped on end.

The present invention also provides a transit package containing at least one screen printing cylinder having within it at least one bag ,which has been filled under pressure so as to form a rigid body which reinforces the screen printing cylinder internally against inward crushing or collapse. Conveniently the bag is filled with small beads of expanded polystyrene.

One particular method according to the invention will now be described, by way of example, with refer- 2 ence to the accompanying semi-diagrammatic drawings in which:

FIG. 1 is a perspective view of a transit package for a plurality of screen printing cylinders enclosed in a packing case, shown in broken lines,

FIG. 2 is a longitudinal sectional view of the package shown in FIG. 1, and

FIG. 3 is a cross-section, on the line llllll of FIG. 2.

Referring to the drawing, the reference numeral 10 indicates an assembly of several screen printing cylinders which have been temporarily deformed or given a kidney-like cross-section, as shown, so that they can be inserted one within the other for transit even although they are normally of the same diameter.

The assembly of cylinders is slid into an elongated packing case 11 of, for example, cardboard orsome other material, the outermost cylinder being a snug fit in the packing case. A suitably shaped elongated block 12 of polymeric material such as expanded polystyrene is inserted, as a snug sliding fit, centrally into the assembly of cylinders so as to extend for the whole length thereof. Further polystyrene or other packing may be provided between the assembly of cylinders and the interior surfaces of the packing case as may be required to hold the assembly firmly in the packing case.

Two identical elongated tubular bags 13 of POLY- THENE are then inserted, in a flat condition and in side-by-side relationship, through the assembly of cylinders and so that the ends 13a of the bags extend well beyond both ends of the assembly of cylinders.

The ends of the bags at one end of the assembly of cylinders are then sealed by means of clips or ties 14. The other ends of the bags are similarly sealed but only after the nozzles, of a pressurized air filling apparatus for the bags, have been inserted thereinto.

The said filling apparatus is then operated so that the bags are charged under pressure with a mass of small beads of polystyrene. As the charging operation involves the use of air under pressure the bags 13 have previously been perforated with a multiplicity of very minute perforations so as to allow the air to escape whilst leaving the polystyrene beads within the bags.

The charging operation is continued until both bags have been very tightly packed with the polystyrene beads and bear firmly and rigidly against the assembly of printing cylinders and project, say 2 or 3 inches, beyond the ends thereof. The charging nozzles are then removed and the bags tightly sealed by means of the clips or ties 14.

The extended ends 13a of the bags 13 are then sealed, by a heat sealing process. as indicated at 15, and tucked into the ends of the cardboard packing case. The packing case is then closed completely and securely by means of cardboard end pieces 16.

The result is a firm and strong package which can, for example, withstand the weight of a person or being dropped from quite a considerable height without any damage to the screens within it.

To unpack the screens one end of the packing case is removed as are also the bag sealing clips 14 at that end of the packing case. This enables some of the polystyrene beads to be worked or discharged into the unfilled ends 13a, of the bags. The resultant reduction in diameter or loosening of the bags enables the screen cylinders to be withdrawn from the packing case.

Before being inserted into the packing case the screen printing cylinders may be enclosed exteriorly in a double walled sock or wrapping, the spaces between 3 the walls, of said sock or wrapping, being subsequently charged under pressure with polystyrene beads so as to fill any cavities between the cylinders and the interior surfaces of the packing case. Thus, the screen printing cylinders are firmly encompassed externally and tightly packed internally with the polystyrene beads and a very robust package is the result.

I claim:

1. A transit package having packed within it at least one screen printing cylinder reinforced internally by two expansible bags, filled with material in particulate form, in spaced parallel relationship and a reinforcing block located between the expansible bags so as to occupy any space therebetween when the latter are filled, forming a substantially rigid body which bears firmly against the wall of the cylinder or against a part of the screen printing cylinder to reinforce it against inward crushing and collapse.

3. A method in accordance with claim 2, wherein said at least one screen printing cylinder is the inner cylinder of an assembly of such cylinders packed one within another, the outer cylinder of the assembly being deformed temporarily to a flattened oval shape and the inner ones to a shape of kidney-like cross-section.

4. A method in accordance with claim 2, wherein the ends of the expansible bags project beyond the ends of said at least one screen printing cylinder.

5. A method in accordance with claim 2, wherein the said at least one screen printing cylinder is enclosed in a packing carton in which the cylinder is a snug fit.

6. A method in accordance with claim 2, wherein the material in particulate form comprises beads of an expanded polymeric material.

7. A method in accordance with claim 2, wherein the expansible bags are made of a flexible plastics material and are perforated with a multiplicity of small perforations.

8. A method in accordance with claim 2, wherein the expansible bags when positioned in the cylinder are in the form of elongated open-ended tubes, one end being sealed before filling the bags under pressure the other end being sealed after filling the bags under pressure. 

1. A transit package having packed within it at least one screen printing cylinder reinforced internally by two expansible bags, filled with material in particulate form, in spaced parallel relationship and a reinforcing block located between the expansible bags so as to occupy any space therebetween when the latter are filled, forming a substantially rigid body which bears firmly against the wall of the cylinder or against a part or parts thereof.
 2. A method of packaging at least one screen printing cylinder which includes the steps of positioning two expansible bags in spaced parallel relationship within the interior of said screen printing cylinder, inserting a reinforcing block within said screen printing cylinder to occupy the space between the two expansible bags when expanded, and filling said bags under pressure with a material in particulate form so as to form a substantially rigid body which bears firmly against the wall of the screen printing cylinder to reinforce it against inward crushing and collapse.
 3. A method in accordance with claim 2, wherein said at least one screen printing cylinder is the inner cylinder of an assembly of such cylinders packed one within another, the outer cylinder of the assembly being deformed temporarily to a flattened oval shape and the inner ones to a shape of kidney-like cross-section.
 4. A method in accordance with claim 2, wherein the ends of the expansible bags project beyond the ends of said at least one screen printing cylinder.
 5. A method in accordance with claim 2, wherein the said at least one screen printing cylinder is enclosed in a packing carton in which the cylinder is a snug fit.
 6. A method in accordance with claim 2, wherein the material in particulate form comprises beads of an expanded polymeric material.
 7. A method in accordance with claim 2, wherein the expansible bags are made of a flexible plastics material and are perforated with a multiplicity of small perforations.
 8. A method in accordance with claim 2, wherein the expansible bags when positioned in the cylinder are in the form of elongated open-ended tubes, one end being sealed before filling the bags under pressure the other end being sealed after filling the bags under pressure. 